I found the Medela sleep bras very comfy for sleeping. As above, they are not super supportive but are nice for around the house and night time.

I was a 32F while nursing and these were absolutely miserable and uncomfortable for me. If you have a small(er) chest and a larger cup, they WILL not fit.

I used the tank tops in the link with nursing pads tucked in, and not only were they more supportive, but they are super comfortable. (at least for me) I can't tell from the picture in the link, but the ones I've purchased in store have comfy shelf bras inside. It's easy to just drop a strap and nurse.